In the conventional synchronous motor described in Patent Literature 1, a plurality of teeth having toroidal windings wound are provided at unequal pitches in a stator in order to facilitate assembly work, the shapes of the teeth being alternately different, and holes for fixing are provided in teeth larger in width along a rotational direction from among the plurality of teeth. In the conventional synchronous motor described in Patent Literature 2, there are 8 poles and 12 slots for the relationship between the number of magnetic poles and the number of slots, and teeth different in width are alternately arranged in a rotational direction on an annular core back. In the conventional synchronous motor described in Patent Literature 3, in order to reduce torque ripples and cogging torque, a stator is used in which, from among a plurality of teeth, the shape of the teeth forming phase 1 or phase 2 is different from those of the teeth forming the other phases.